Medical microbiology

Medical microbiology

1. MEDICAL MICROBIOLOGY Saturday, 21 October, 2017 1

2. OUTLINE INTRODUCTION TO MEDICAL MICROBIOLOGY HISTORY OF MEDICAL MICROBIOLOGY FIELDS IN MEDICAL MICROBIOLOGY FUNGAL INFECTIOUS DISEASE PARASITIC DISEASE VIRAL INFECTIOUS DISEASE BACTERIAL INFECTIOUS DISEASE DIAGNOSIS IN MEDICAL MICROBIOLOGY AND TREATMENT Saturday, 21 October, 2017 MEDICAL MICROBIOLOGY 2

3. MEDICAL MICROBIOLOGY Medical microbiology  is a branch of  medicine  concerned with the prevention, diagnosis and treatment of infectious diseases. In addition, this field of science studies various clinical applications of microbes for the improvement of health. There are four kinds of  microorganisms  that cause infectious disease:  bacteria ,  fungi ,  parasites  and  viruses . Saturday, 21 October, 2017 3 MEDICAL MICROBIOLOGY

4. Medical microbiology , also known as ‘’’clinical microbiology’’’, is the study of  microbes , such as  bacteria ,  viruses ,  fungi  and  parasites , which cause a human illness and their role in the disease. Medical microbiologist is also involved in teaching at all levels, and in research. It provided the development of vaccines against invading organisms . Saturday, 21 October, 2017 4 MEDICAL MICROBIOLOGY

5. Deadly and debilitating diseases such as small pox, polio, and tuberculosis have been either eradicated or become more treatable. There are claims that consuming probiotics (bacteria potentially beneficial to the digestive system) and/or prebiotics (substances consumed to promote the growth of probiotic microorganisms) contributes to human health.  Microorganisms could be useful in the treatment of cancer. Strains of non-pathogenic clostridia can infiltrate and replicate within solid tumours, deliver therapeutic proteins. Saturday, 21 October, 2017 5 MEDICAL MICROBIOLOGY

6. HISTORY OF MEDICAL MICROBIOLOGY In 1546,  Girolamo Fracastoro  proposed that epidemic diseases were caused by transferable seed like entities through direct, indirect contact and contact over long distances with an infection. Louis Pasteur  and  Robert Koch  are the founders of medical microbiology. Louis Pasteur is famous for his experiments when he disproved the theory of spontaneous generation. He offered method for food preservation (pasteurization) and vaccines against anthrax, fowl cholera and rabies . Robert Koch contributed to the germ theory of disease, provided that specific diseases were caused by specific microbes. He developed criteria known as the Koch's postulates and was among first to isolate bacteria in pure culture resulting in his description of several bacteria including Mycobacterium tuberculosis, the causative agent of tuberculosis Saturday, 21 October, 2017 6 MEDICAL MICROBIOLOGY

7. medical  microbiologist  studies the characteristics of  pathogens , their modes of transmission, mechanisms of infection and growth . Saturday, 21 October, 2017 7 MEDICAL MICROBIOLOGY

8. medical microbiology primarily focuses on the presence and growth of microbial infections in individuals, their effects on the human body and the methods of treating those infections . Saturday, 21 October, 2017 8 MEDICAL MICROBIOLOGY

9. In 1676,  Anton van Leeuwenhoek  observed bacteria and other microorganisms, using a single-lens  microscope  of his own design Saturday, 21 October, 2017 9 MEDICAL MICROBIOLOGY

10. Smallpox is a deadly disease caused by the  variola  virus. It causes painful lesions that leave disfiguring scars on the skin of people who survive, and can also cause blindness. However, many infected people do not survive. Smallpox had a fatality rate ranging from 20-60% in adults and even higher in infants. Saturday, 21 October, 2017 10 MEDICAL MICROBIOLOGY

11. In 1796, Jenner decided to test whether you could transmit cowpox to healthy people on purpose in order to immunize them against smallpox. He called this procedure vaccination from the Latin wordvacca, which means cow. Jenner tested vaccination on an 8-year old boy and it worked! The boy didn't get smallpox when experimentally infected with it a couple months late Saturday, 21 October, 2017 11 MEDICAL MICROBIOLOGY

12. In 1857 Louis Pasteur also designed vaccines against several diseases such as  anthrax,fowl  cholera and rabies as well as pasteurization for food preservation. Saturday, 21 October, 2017 12 MEDICAL MICROBIOLOGY

13. 1867 Joseph Lister is considered to be the father of antiseptic surgery. By sterilizing the instruments with diluted carbolic acid and using it to clean wounds, post-operative infections were reduced making surgery safer for patients. Saturday, 21 October, 2017 13 MEDICAL MICROBIOLOGY

14. Robert Koch contributed to the germ theory of disease, provided that specific diseases were caused by specific microbes. He developed criteria known as the Koch's postulates and was among first to isolate bacteria in pure culture resulting in his description of several bacteria including Mycobacterium tuberculosis, the causative agent of tuberculosis . Saturday, 21 October, 2017 14 MEDICAL MICROBIOLOGY

15. Fields in medical microbiology Microbial physiology  is the study of microbial growth, microbial  metabolism  and  microbial cell structure . Microbial genetics  is the study of how  genes  are organized and regulated in  microbes  in relation to their cellular functions. Parasitology  investigates parasites. The specimen here is  feces ,  blood ,  urine ,  sputum , and other samples. Virology  identifies  viruses  in specimens of  blood ,  urine , and  cerebrospinal fluid . Immunology / Serology  uses antigen-antibody interaction as a diagnostic tool, determines compatibility of transplanted organs. A medical microbiologist is a specialist in medical (clinical) microbiology. Saturday, 21 October, 2017 15 MEDICAL MICROBIOLOGY

16. Fungal infectious diseases The diseases that are caused by the pathogenic fungi species such as candida,histoplasmia etc.fungal infectous diseases include histoplasmosis and many others. Saturday, 21 October, 2017 16 MEDICAL MICROBIOLOGY

17. Transmission of infectious diseases:- There are various ways in which disease can be transmitted between individuals. These include Direct contact - Touching an infected host. Indirect contact - Touching a contaminated surface Droplet contact  - Coughing or sneezing Fecal–oral route  - Ingesting contaminated food or water sources Saturday, 21 October, 2017 17 MEDICAL MICROBIOLOGY

18. Airborne transmission  - Pathogen carrying spores Vector transmission  - An organism that does not cause disease itself but transmits infection by conveying pathogens from one host to another Fomite transmission  - An inanimate object or substance capable of carrying infectious germs or parasites Environmental  - Nosocomial infections Saturday, 21 October, 2017 18 MEDICAL MICROBIOLOGY

19. Histoplasmosis :- Alternative Names:- Ohio River Valley fever; Fibrosing mediastinitis Causes of histoplasmosis :- Histoplasmosis is an infection caused by a fungus called  Histoplasma .  fungus lives in the environment, particularly in soil that contains large amounts of bird or bat droppings. People can get histoplasmosis after breathing in the microscopic fungal spores from the air,or often after participating in activities that disturb the soil. Saturday, 21 October, 2017 19 MEDICAL MICROBIOLOGY

20. 4-The spores are extremely light and float into the air when dirt or other contaminated material is disturbed. 5- Even if you've had histoplasmosis in the past, you can still get the infection again. Symptoms of histoplasmosis :- Fever cough Fatigue (extreme tiredness) Chills Saturday, 21 October, 2017 20 MEDICAL MICROBIOLOGY

21. Symptoms :- Headache Chest pain Body aches histoplasmosis can also produce joint pain chronic form of histoplasmosis that can additionally feature weight loss and a cough that brings up blood. long-term (chronic). Symptoms include: 1- Chest pain and shortness of breath 2- Cough, possibly coughing up blood 3- Fever and sweating Saturday, 21 October, 2017 21 MEDICAL MICROBIOLOGY

22. Life cycle of histoplasma :- . When people breathe in the spores, they are at risk for developing histoplasmosis . After the spores enter the lungs, the person’s body temperature allows the spores to transform into yeast. The yeast can then travel to lymph nodes and can spread to other parts of the body through the bloodstream. Saturday, 21 October, 2017 22 MEDICAL MICROBIOLOGY

23. Life cycle of histoplasma :- Saturday, 21 October, 2017 23 MEDICAL MICROBIOLOGY

24. Complications of histoplasmosis :- Histoplasmosis can cause a number of serious complications, Complications can include: Acute respiratory distress syndrome (ARDS). Histoplasmosis can damage lungs to the point that the air sacs begin filling with fluid. This prevents efficient air exchange and can deplete oxygen levels in the blood. Heart problems. Inflammation of the pericardium, the sac that surrounds your heart, is called pericarditis . When the fluid in this sac increases, it can interfere with the heart's ability to pump blood efficiently. Saturday, 21 October, 2017 24 MEDICAL MICROBIOLOGY

25. Adrenal insufficiency.   Histoplasmosis can harm your adrenal glands, which produce hormones that give instructions to virtually every organ and tissue in your body. Meningitis.  In some cases, histoplasmosis can cause meningitis, an infection and inflammation of the membranes surrounding your brain and spinal cord. Saturday, 21 October, 2017 25 MEDICAL MICROBIOLOGY

26. Exams and test:- Histoplasmosis is diagnosed by: Biopsy of the lung, skin, liver, or bone marrow Blood or other tests to detect histoplasmosis proteins or antibodies Cultures of the blood, and other things (this test provides the clearest diagnosis of histoplasmosis , but results can take 6 weeks) Saturday, 21 October, 2017 26 MEDICAL MICROBIOLOGY

27. Treatment:- The main treatment for histoplasmosis is antifungal drugs. Amphotericin B, itraconazole , and ketoconazole are the usual treatments. Antifungals may need to be given through a vein, depending on the form or stage of disease. Prevention :- Histoplasmosis may be prevented by reducing exposure to dust in chicken coops, bat caves, and other high-risk locations. Wear masks and other protective equipment if you work in these environments. Saturday, 21 October, 2017 27 MEDICAL MICROBIOLOGY

28. -: Histoplasmosis in lungs:- Saturday, 21 October, 2017 28 MEDICAL MICROBIOLOGY

29. Definition: A parasitic disease is an infectious disease caused or transmitted by a parasite. Many parasites do not cause diseases. Parasitic diseases can affect practically all living organisms, including plants and mammals. The study of parasitic diseases is called parasitology. Saturday, 21 October, 2017 29 MEDICAL MICROBIOLOGY

30. Symptoms: Abdominal pain. Weight loss. Increased appetite. Sleeping problems. Vomiting. Fatigue. Dehydration. Saturday, 21 October, 2017 30 MEDICAL MICROBIOLOGY

31. Cause Mammals can get parasites from contaminated food or water andbug bites. Other risks are walking barefeet , inadequate disposal of faeces and eating undercooked or exotic food. Parasites can also be transferred to their host by the bite of an insect vector, i.e. mosquitos. Saturday, 21 October, 2017 31 MEDICAL MICROBIOLOGY

32. E. Histolytica Geographical distribution : E. histolytica is more common in tropical and sub-tropical countries. In India it occasionally takes an epidemic form. It is estimated that about seven to eleven per cent of the population in India suffers from its infection. Saturday, 21 October, 2017 MEDICAL MICROBIOLOGY 32

33. Entamoeba histolytic Parasitic Protozoans cause Amoebiasis Infective stage Tetra nucleated cyst Host Human Portal of entry Mouth Mode of reproduction Binary fission Habitat Colon and caecum Mode of transmission Ingestion of mature cyst through contaminated food or water Saturday, 21 October, 2017 33 MEDICAL MICROBIOLOGY

34. Life cycle: E. histolytica is a monogenetic parasite as its life cycle is completed in a single host i.e., man. Infection by Entamoeba histolytica occurs by ingestion of mature cysts in fecal contaminated food, water, or hands. Excystation occurs in the small intestine and trophozoites are released, which migrate to the large intestine. The trophozoites multiply by binary fission and produce cysts , which are passed in the feces. Because of the protection conferred by their walls, the cysts can survive days to weeks in the external environment and are responsible for transmission. Saturday, 21 October, 2017 MEDICAL MICROBIOLOGY 34

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36. Viral infections A viral infection occurs when an organism's body is invaded by pathogenic viruses.  Structural characteristics, such as genome type, virion shape and replication site, generally have the same features among virus species within the same family. There are currently 21 families of viruses known to cause disease in humans. Study of viral infection is also known as virology. Saturday, 21 October, 2017 36 MEDICAL MICROBIOLOGY

37. Diagnosis & treatment Viral disease can be detected by severe muscle and joint pains before fever and also by skin rash and lymph gland swelling . Viruses commonly have self-limited life, so treatment is usually reduce the symptoms only. Antipyretic and Analgesic drugs are commonly be used . Saturday, 21 October, 2017 37 MEDICAL MICROBIOLOGY

38. 1.Measles : Measles is an infectious disease caused by a measle virus . It is a single-stranded, negative-sense, enveloped RNA virus of the genus Morbillivirus within the family Paramyxoviridae . Virus lives in the mucous of nose and throat of infected person . It spreads easily from person to person by coughing and sneezing into the air. Infected droplets of mucous can remain active and contagious for around two hours. Means ,virus live outside the body.e.g on surfaces and door handles . Saturday, 21 October, 2017 38 MEDICAL MICROBIOLOGY

39. Symptoms : Saturday, 21 October, 2017 39 MEDICAL MICROBIOLOGY

40. Conjunctivitis (pink eye) Measle virus Saturday, 21 October, 2017 40 MEDICAL MICROBIOLOGY

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42. Treatment : Measles can be diagnosed by symptoms like,rash and small spots on body. But,a simple blood or saliva test can also be diagnosed. No specific medicine that kills measles virus. Treatment with vitamin A offered to infected people. Saturday, 21 October, 2017 42 MEDICAL MICROBIOLOGY

43. 2.Diarrhea It is caused by Rotavirus among infants and young children. Name comes from its characteristic wheel-like appearance of virus when viewed by electron microscopy. It is a genus of non-enveloped, double-stranded RNA virus in the family Reoviridae . Virion shape: icosahedral Replication site: cytoplasm It infects & damages the cells of small intestine causes gastroenteritis . Saturday, 21 October, 2017 43 MEDICAL MICROBIOLOGY

44. Rotavirus 20 sided body 65-75nm Nucleus : 45-50 nm Shape : wheel like Life : 7m Saturday, 21 October, 2017 MEDICAL MICROBIOLOGY 44

45. Symptoms: Vomiting Low fever dizziness while standing decrease in urination dry mouth and throat. Saturday, 21 October, 2017 45 MEDICAL MICROBIOLOGY

46. Transmission: Rotavirus infection is highly contagious. The primary mode of transmission of rotavirus is the passage of the virus in stool to the mouth of another child. This is known as a fecal-oral route of transmission. Virus is stable (remains infective) in the environment, transmission can occur through ingestion of contaminated water or food and contact with contaminated surfaces. Rotavirus can survive for days on hard and dry surfaces, and it can live for hours on human hands. Saturday, 21 October, 2017 46 MEDICAL MICROBIOLOGY

47. Diagnosis & treatment: Infection can be diagnosed by gastroenteristics as the cause of severe diarrhoea . Also by finding in the child’s stool by enzyme immunoassay. Treatment is non-specific . involves management of symptoms and, most importantly, maintenance of hydration. If untreated, children can die from the resulting severe dehydration . Saturday, 21 October, 2017 47 MEDICAL MICROBIOLOGY

48. ORS (oral rehydration solution) also given to child in which small amounts of salt and sugar containing extra water, for treatment depending on severity of diarrhoea . In some cases, fluids are given by intravenous ( within vein) drip . Saturday, 21 October, 2017 48 MEDICAL MICROBIOLOGY

49. BACTERIAL INFECTIOUS DISEASE Saturday, 21 October, 2017 49 MEDICAL MICROBIOLOGY

50. Tuberculosis Tuberculosis, commonly known as TB, is a bacterial infection that can spread through the lymph nodes and bloodstream to any organ in your body. It is most often found in the lungs. Saturday, 21 October, 2017 50 MEDICAL MICROBIOLOGY

51. S ymptoms Although your body may harbor the bacteria that cause tuberculosis, your immune system usually can prevent you from becoming sick. For this reason, doctors make a distinction between: Latent TB. In this condition, you have a TB infection, but the bacteria remain in your body in an inactive state and cause no symptoms. Latent TB, also called inactive TB or TB infection, isn't contagious. It can turn into active TB, so treatment is important for the person with latent TB and to help control the spread of TB in general . Saturday, 21 October, 2017 51 MEDICAL MICROBIOLOGY

52. An estimated 2 billion people have latent TB. Active TB. This condition makes you sick and can spread to others. It can occur in the first few weeks after infection with the TB bacteria, or it might occur years later. Saturday, 21 October, 2017 52 MEDICAL MICROBIOLOGY

53. Signs and symptoms Coughing that lasts three or more weeks Coughing up blood Chest pain, or pain with breathing or coughing Unintentional weight loss Fatigue Fever Chills Loss of appetite Saturday, 21 October, 2017 53 MEDICAL MICROBIOLOGY

54. C auses Tuberculosis is caused by bacteria that spread from person to person through microscopic droplets released into the air . This can happen when someone with the untreated, active form of tuberculosis coughs, speaks, sneezes, spits, laughs or sings. Saturday, 21 October, 2017 54 MEDICAL MICROBIOLOGY

55. Prevention Follow these tips to help keep others from getting sick Stay home Ventilate the room Cover your mouth Wear a mask   Saturday, 21 October, 2017 55 MEDICAL MICROBIOLOGY

56. DIAGONOSIS IN MEDICAL MICROBIOLOGY Saturday, 21 October, 2017 56 MEDICAL MICROBIOLOGY

57. Diagnosis types Saturday, 21 October, 2017 57 MEDICAL MICROBIOLOGY

58. 1-Microbial culture The primary method used for isolating infectious disease for study in the laboratory. Tissue or fluid samples are tested for the presence of a specific pathogen, which is determined by growth in a selective or differential medium . Culture is microbial growth on or in a nutritional solid or liquid medium; increased numbers of organisms simplify identification. Saturday, 21 October, 2017 58 MEDICAL MICROBIOLOGY

59. Types of Culture Solid culture Liquid culture Cell culture Solid state containing salt and agar. Microbial growth is determined by the time taken for the liquid to form a colloidal suspension. Human or animal cell cultures are infected with the microbe of interest. Used to culture bacteria and fungi. Used for diagnosing parasites and detecting mycobacteria. Identifying viruses. Saturday, 21 October, 2017 59 MEDICAL MICROBIOLOGY

60. 2-Microscopy Microscopic examination can provide a preliminary, tentative identification of certain infectious agents by revealing their size, shape, and cellular structure. It includes the staining technique for identification of infectious agent. Staining includes a) Gram stain test. b) Acid fast stain test. c) Fluorescent stains. Saturday, 21 October, 2017 60 MEDICAL MICROBIOLOGY

61. c ) Trichrome stain d) Warthin -Starry stain and Dieterle stain a)Gram stain test in which a sample is smeared on a microscopic slide and stained with a special dye—is used to classify all bacteria as either gram positive (blue staining) or gram negative (red staining ) b )Acid-fast and moderate (modified) acid-fast stains used to identify acid-fast organisms (Mycobacterium sp ) and moderately acid-fast organisms (primarily Nocardia sp ). Saturday, 21 October, 2017 61 MEDICAL MICROBIOLOGY

62. These stains are also useful for staining Rhodococcus and related genera, as well as oocysts of some parasites (e.g. Cryptosporidium ). c )Fluorescent stains: These stains allow detection at lower concentrations Examples acridine orange (bacteria and fungi) auramine-rhodamine and auramine O (mycobacteria ) calcofluor white (fungi, especially dermatophytes) Saturday, 21 October, 2017 62 MEDICAL MICROBIOLOGY

63. d) Warthin-Starry stain and Dieterle stain These silver stains are used to visualize bacteria such as spirochetes, Helicobacter pylori, microsporidia , and Bartonella henselae (the cause of cat-scratch disease). Saturday, 21 October, 2017 63 MEDICAL MICROBIOLOGY

64. 3-Biochemical test Enzymatic activities are widely used to differentiate bacteria. Even closely related bacteria can usually be separated into distinct species by subjecting them to biochemical tests. Example Enteric , gram-negative bacteria are a large heterogeneous group of microbes whose natural habitat is the intestinal tract of humans and other animals . All members of the family Enterobacteriaceae are oxidase-negative Saturday, 21 October, 2017 64 MEDICAL MICROBIOLOGY

65. Rapid identification method An unknown enteric bacterium is inoculated into a tube designed to perform 15 biochemical tests . After incubation, results in each compartment are recorded. E ach test is assigned a value; the number derived from scoring all the tests is called the ID value. Fermentation of glucose is important, and a positive reaction is valued at 2, compared with the production of acetoin (V-P test, or the Voges-Proskauer test) which has no value. Saturday, 21 October, 2017 65 MEDICAL MICROBIOLOGY

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67. Agglutination test S lide agglutination test, samples of an unknown bacterium are placed in a drop of saline on each of several slide D ifferent known antiserum is added to each sample. The bacteria agglutinate (clump) when mixed with antibodies that were produced in response to that species or strain of bacterium ; a positive test is indicated by the presence of agglutination . Saturday, 21 October, 2017 67 MEDICAL MICROBIOLOGY

68. TREATMENT Some infections can be dealt with by the body’s own immune system, but more serious infections are treated with antimicrobial drugs. Bacterial infections are treated with antibacterial (often called antibiotics) whereas fungal and viral infections are treated with antifungals and antivirals respectively. A broad class of drugs known as antiparasitics are used to treat parasitic diseases. Saturday, 21 October, 2017 68 MEDICAL MICROBIOLOGY

69. THANK YOU Saturday, 21 October, 2017 69 MEDICAL MICROBIOLOGY